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151.
In this paper we report the anaerobic Escherichia coli biofilm formation on solid substrate under redox-controlled extracellular environment by an electrochemical quartz crystal microbalance (EQCM) method. Both biomass and electrochemical activity were monitored in situ. Larger biomass was yielded under redox-controlled condition comparing with natural biofilm growth, which was also confirmed by optical observation. Surface-colonizing cells responded more sensitively to their redox environment than planktonic cells. Cyclic voltammogram (CV) obtained during the time course of biofilm development indicates the emergence of redox active phenotype under redox-controlled condition but not in natural condition. Our results suggest an effective means to control biofilm development with desired metabolic adaptation and also to in situ monitor the biomass yield and the emergent catalytic property simultaneously. 相似文献
152.
Jie Li Chuanjiang Li Zi‐Liang Wang 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(12):m384-m386
The asymmetric unit of the title two‐dimensional coordination polymer, {[Cd(C14H8O4)(C14H14N4)]·0.15H2O}n, is composed of one CdII cation, one biphenyl‐2,4′‐dicarboxylate (bpdc) anion, one 1,4‐bis(imidazol‐1‐ylmethyl)benzene (bix) ligand and 0.15 solvent water molecules. The coordination environment of the CdII cation is defined by four carboxylate O atoms from two different bpdc anions in a chelating mode and two N atoms from two distinct bix ligands, constructing a distorted trigonal prism polyhedron. Two inversion‐related CdII cations are bridged together by two positionally disordered bpdc anions, forming a 22‐membered ring with a Cd...Cd distance of 9.1966 (9) Å. These rings are then further linked by two bix ligands, extending into a two‐dimensional layer along (102) with 63 topology. 相似文献
153.
Guang‐Hui Zhao Juan Li Rui‐Qing Lin Feng‐Cai Zou Wei Liu Zi‐Guo Yuan Xi‐Hao Mo Hui‐Qun Song Ya‐Biao Weng Xing‐Quan Zhu 《Electrophoresis》2010,31(4):641-647
In the present study, restriction site‐amplified polymorphism (RSAP) markers were used to examine the genetic variability of Schistosoma japonicum isolates from different endemic provinces in mainland China. Of the 45 pairs of primers screened, 10 RSAP markers showed a clear banding pattern with good resolution; however, only six exhibited a polymorphism among different isolates. Among six RSAP markers, one pair of primers (R8+R10) was able to differentiate male and female parasites, and amplified one constant specific band for female S. japonicum isolates. The specific band was recovered, re‐amplified and sequenced, and a sequence of 162 bp was obtained. Based on this sequence, a pair of specific primers was designed and used to develop sequence characterized amplified region (SCAR)‐PCR assay for identification and differentiation of female S. japonicum isolates. The SCAR‐PCR assay allowed the specific identification of female S. japonicum, with no amplicons being amplified from male S. japonicum, Fasciola hepatica, Clonorchis sinensis, S. mansoni (male and female parasite). DNA sequencing confirmed the identity of the amplified products. The minimum amount of DNA detectable using SCAR‐PCR assay was 0.3 ng for female S. japonicum. The SCAR‐PCR was able to differentiate effectively the male and female S. japonicum worms collected from 12 geographical origins in eight endemic provinces, the gender of which was known based on the morphological and biological features. These results showed that SCAR‐PCR provides an effective tool for the sex differentiation studies of S. japonicum, identification of female S. japonicum, diagnosis and epidemiological survey of S. japonicum infections in animals and human. 相似文献
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157.
In this paper, an equivalent relation among the reflexivity, weak sequential completeness and bounded completeness in full function space is given. Some results on weakly sequential compactness of subset and the property (u) in substitution spaces are obtained. 相似文献
158.
Zhi Ping Xu Zi Gu Xiaoxi Cheng Firas Rasoul Andrew K. Whittaker Gao Qing Max Lu 《Journal of nanoparticle research》2011,13(3):1253-1264
A novel nanocomposite film for sustained release of anionic ophthalmic drugs through a double-control process has been examined
in this study. The film, made as a drug-loaded contact lens, consists principally of a polymer hydrogel of 2-hydroxyethyl
methacrylate (HEMA), in whose matrix MgAl-layered double hydroxide (MgAl-LDH) nanoparticles intercalated with the anionic
drug are well dispersed. Such nanocomposite films (hydrogel-LDH-drug) contained 0.6–0.8 mg of MgAl-LDH and 0.08–0.09 mg of
the ophthalmic drug (ketorolac) in 1.0 g of hydrogel. MgAl-drug-LDH nanoparticles were prepared with the hydrodynamic particle
size of 40–200 nm. TEM images show that these nanoparticles are evenly dispersed in the hydrogel matrix. In vitro release
tests of hydrogel-LDH-drug in pH 7.4 PBS solution at 32 °C indicate a sustained release profile of the loaded drug for 1 week.
The drug release undergoes a rapid initial burst and then a monotonically decreasing rate up to 168 h. The initial burst release
is determined by the film thickness and the polymerization conditions, but the following release rate is very similar, with
the effective diffusion coefficient being nearly constant (3.0 × 10−12 m2/s). The drug release from the films is mechanistically attributed to anionic exchange and the subsequent diffusion in the
hydrogel matrix. 相似文献
159.
Polymer electrolyte membranes, comprising of poly(methyl methacrylate) (PMMA), lithium tetraborate (Li2B4O7) as salt and dibutyl phthalate (DBP) as plasticizer were prepared using a solution casting method. The incorporation of DBP
enhanced the ionic conductivity of the polymer electrolyte. The polymer electrolyte containing 70 wt.% of poly(methyl methacrylate)–lithium
tetraborate and 30 wt.% of DBP presents the highest ionic conductivity of 1.58 × 10−7 S/cm. The temperature dependence of ionic conductivity study showed that these polymer electrolytes obey Vogel–Tamman–Fulcher
(VTF) type behaviour. Thermogravimetric analysis (TGA) was employed to analyse the thermal stability of the polymer electrolytes.
Fourier transform infrared (FTIR) studies confirmed the complexation between poly(methyl methacrylate), lithium tetraborate
and DBP. 相似文献
160.